The present invention relates to a spray tip and a method of forming a spray tip and, in particular, to a metal spray tip for a fluid spray nozzle and method of forming such tip in which at least a portion of the exterior surfaces of the spray tip are coated with a colored coating.
Spray tips having a wide variety of sizes and shapes of spray orifices and, hence, a wide range of flow rates, have been employed in a vast range of differing uses. Such tips are generally installed in nozzle bodies which hold the tip and transmit the fluid to be sprayed thereto where the orifice meters the fluid and shapes the spray discharge into its desired shape and patternation. Thereby, the tip orifice actually determines the flow rate of the nozzle at any given fluid pressure, and in a given use, such as in the spraying of agricultural chemicals, a particular tip having a given sized metering orifice is selected for use in these nozzle bodies depending upon the flow rate desired by the user for that particular use.
Such spray tips are frequently quite small and, as a result of their size, are either incapable of carrying adequate markings on the tip itself which might visually indicate the capacity of a given tip or, if such markings can be carried on the tip, they either must be in a short code or are frequently so small as to be difficult to visually observe. It is also a frequent occurrence that markings, if they are present on the tip, are obscured by the nozzle body itself after the tip is installed in the nozzle body or by the liquid being sprayed during use. Thus, it is usually difficult, if not impossible, to visually determine just what the flow rate is of a given nozzle even if the spray tip is marked without either disassembling the nozzle body or subjecting the person making that determination to contact with the fluid which is being sprayed.
In order to overcome these aforementioned identification difficulties, several approaches have been employed in the past which involve color coding either the spray tips or some portion of the nozzle body for rapid identification of the flow rates of given tips or nozzle assemblies.
One manner of color coding comprises wrapping tape about either the nozzle body or the nozzle tip in a recess or recesses therein. The disadvantage of this method of identification is that the tape tends to loosen and become lost in use and recesses may be difficult to form in extremely small nozzle tips.
Another method of color coding consists of molding the entire nozzle tip of a colored plastic material. Although this method overcomes the difficulty of loss of the color identification in use and lack of availability of space for color coded recesses, the plastic has certain inherent disadvantages over metals, such as brass or steel. For example, the use of plastic requires special machinery to replace the machinery previously conventionally used for the forming of metal spray tips, custom making of tips to order is generally more difficult than with metal tips, and durability may not be as good in some plastic tips as in metal tips. Moreover, the precision of some plastic tips may not be as good as the corresponding machined metal tip.
Other color coding methods have also included the painting of colored dots on portions of the nozzle assembly other than the spray tip itself, for example on the tip retainer ring. One of the disadvantages of this procedure is that the color coding is effective only so long as care is taken to change the retainer ring at the same time as the nozzle tip. If the retainer ring is not changed when a tip is changed to a different flow rate, the coding on the nozzle is no longer indicative of the flow rate on the actual tip then being used in the nozzle and the coding, in fact, actually becomes misleading.
The spray tips and methods of forming the tips of the present invention overcome these several disadvantages. In the present invention a nozzle spray tip may be formed of metal, thereby, realizing all of the inherent advantages of metal. Yet, such metal tips may be color coded so as to give a ready indication of the flow rate of the spray tips to an observer having knowledge of the code. Because the spray tip of the present invention may be formed of metal, special machinery to form the tip is not necessary, custom making of the tips is facilitated, and durability and precision of the spray tips in use may be improved. Moreover, the spray tip incorporating the principles of the invention itself is coated with a color coating and, thereby, the identification of the flow rate of that given tip is always accurate in whatever nozzle assembly the tip may be installed. Either the relationship of the flow rates of a plurality of spray tips in a given installation, e.g. an agricultural spray boom, or the flow rate of any given spray tip of the present invention may be readily determined by visual examination, either before installation of the tips or after the tips are in use, and without exposure of the investigator to contamination from the fluid being sprayed. The ability to readily visually determine the flow rate of the nozzles in, for example apparatus for the application of agricultural herbicides and pesticides, can have an added environmental advantage in reducing the amount of such materials which might otherwise enter the environment due to the use of improper oversized tips in such apparatus.
Additionally, in a spray tip incorporating the principles of the present invention, the colored coating on the tip does not impair the precision of the tip and, in some of the preferred embodiments of the tip of the present invention, the metal tip may be coated after it is fully formed with its spray orifice. The ability to coat the tip after the orifice is formed, may eliminate the need for baking to cure the coating, reduce the thickness of the coating, reduce the tendency of the coating to flake or peel, facilitate identification of the nature of the metal used to form the tip both during and after coating has occurred, and facilitate the removal of burrs and cleaning after machining of the tip without damaging the coating.
In one principal aspect of the present invention, a spray tip for a fluid spray nozzle having a spray orifice therein for metering and spraying fluid is provided. The improvement in such tip comprises a colored coating adhering to and covering at least a portion of the exterior surface of the tip adjacent to the spray orifice.
In another principal aspect of the present invention, in the aforementioned spray tip the color of the coating denotes the flow rate of the spray tip.
In still another principal aspect of the present invention, the aforementioned spray tips include a face having the spray orifice therein and the face has the colored coating adhering thereto.
In still another principal aspect of the present invention, the exterior surfaces of the spray tip may be either completely coated or only partially coated so as to expose the material from which the tip is made to visual viewing.
In still another principal aspect of the present invention, the coating may be either an electrostatically deposited or a printed coating.
In still another principal aspect of the present invention, a method of forming a coated spray tip for a fluid spray nozzle comprises the steps of coating a spray tip blank with a colored coating and forming the spray tip orifice in the coated blank and through the coating after the coating has been applied.
In still another principal aspect of the present invention, a method of forming a coated spray tip for a fluid spray nozzle comprises the steps of applying a colored coating by printing the coating on a substantially flat face of the tip such that the coating is absent from the orifice of the spray tip.
In still another principal aspect of the present invention, in the last mentioned method, the orifice is formed in the face before the coating is printed upon the face and the coating image printed upon the face is free of coating at the orifice, but the coating is adjacent to the orifice.
In still another principal aspect of the present invention, a spray tip for a fluid spray nozzle having a spray orifice therein for metering and spraying fluid and a substantially flat exterior face thereon is provided. The improvement in such tip comprises a colored coating adhering to and covering the flat exterior face.
In still another principal aspect of the present invention, in the aforementioned spray tip the color of the coating denotes the flow rate of the spray tip.
In still another principal aspect of the present invention, in the last mentioned spray tips, the spray orifice is in the coated exterior face.
In still another principal aspect of the present invention, the exterior surfaces of the spray tip may be either completely coated or only partially coated so as to expose the material from which the tip is made to visual viewing.
In still another principal aspect of the present invention, the coating may be either an electrostatically deposited or a printed coating.
These and other objects, features and advantages of the present invention will become more readily understood upon a consideration of the following detailed description.